I’m building a 1997 lt1 383 eagle forged balanced crank kit
h beam. Bored .30. My machinist is working the stock heads
It’s only in the planning stages. Machinist has the block and heads.
My questions is mainly on
what cam to use ? I could care less about drivability. I’m using the car for sport, meaning , street race , road race , drag and sporting my 12 yr old around town turning heads.
Injector size?32
throttle body?
intake ?
considering no ac
egr delete , etc.
basically the whole build
doing most of the work myself with lots of advice
ive got someone to do the tune
im finding it difficult to get the folks I know who have the lt1 knowledge to take the time to direct me
my machinist does strictly carbureted / racing builds
so I need help on the duel injection delivery
I would greatly appreciate the advice and anyone that could contact me directly would be most appreciated

building it in my my living room. Most anyone can appreciate this

 

Welcome to CamaroZ28.com ! ! !

Since "New Member Intro" is primarily just for saying "hello", and you are looking for advice on an engine build, let's move this to the "LT1 Based Engine Tech" forum. Much more likely to get help there.

 

What exactly is your goal for this engine? HP at the flywheel? Normally aspirated or power adder (now or in the future)? Is this going into a vehicle with the M6 or A4 trans?

What is the budget? Have you allowed $$$ for the required upgrades to the drivetrain and the suspension?

How well does your "machinist" know the LT1 heads? There are a couple of popular sources for porting the stock heads that have reasonable prices and produce excellent results. Stock LT1 intake is fine, with correct porting, for most applications, unless you are looking for extreme HP and willing to run a converted single-plane intake.

Injectors and throttle body get sized after you know the head flow and the estimated max HP.

If you plan to do the build yourself, I would strongly recommend you get a copy of this book:



The cam selection has to be based on and coordinated with the results of the head porting,

 

Thank you for responding. I’m using the car for horsing around.
More interested in street/ road racing. Not really any drag racing. Hitting the the mountains.
I live in the mountains. Car has 97,000 miles its 6 speed.
Transmission is being rebuilt and new clutch going in.
I am doing all myself. I did by the other lt1/ lt4 book
The target is 425-450 fwhp. So my machinist tells me that’s what the short Block and heads will get me.
He is doing minimal port work on heads mainly the valve job.
Move selected the lunati voodoo cam 60122.
Im thinking a little bigger throttle body 52?
a little bigger injectors.
Staying with the optispark.

No emmisions where I live so good flowing exhaust

Most likely hook back up the ac but delete egr system.

Any how 3200 on short block
$1500 on heads, cam, etc.

part of me wants to throw all the bigger parts on it now
thinking about minimal add ons a tune and go.
Mod up later
around 5 budget but realize it’s closer to 6 +

was a nice car till till I took it apart. 74,000 original miles
leaked oil and need a clutch now here I go.

Reslly appreciate the hrlp.

 

Sorry for typos. Setting it up for 200 shot if I wanted but have no interest. I’m told even how stout we are building bottom end it won’t hold boost.
Originally I was going to have him work the heads and cam it.

I could not resist once I got it apart to tear into the bottom.

 

Hello, I just received my January 2020 copy of "Chevy Performance" and the have an article in it about "Building a 383 the Right Way" and it is very informative and you might want to pick it up as it tells about the math involved in building a 383 and the cam selection referring to the duration and the characteristics of the 383 and why it does this and why it needs that.

I've got a Dart block and head set up with an 871 blower on it and it and had the same on a 350 and what a difference the couple extra cubes made and after reading that article I understood more about why it is.

 

Is the kit the B12111030 with the 6" rods or the B12108030 with the 5.7" rods? What is your target static compression ratio?

The overbore would be 0.030"

That is not going to support 450 HP at the flywheel. Here's good info/pricing on properly ported stock LT1 heads. And, he offers custom cams to more exactly meet your specific driving needs, reflecting the fact this is an EFI engine.

http://elliottsportworks.com/

Your "machinist" seems like he may be locked into Gen 1 SBC technology. The LT1 (Gen 2 SBC) is a different animal. EFI tech is much different than carb tech.


Your requirements are all over the place. Sounds like you need a build with good low end torque, for your "street racing" and "road racing" and "hitting the mountains". Cam selection is critical. Good low RPM torque is going to be more important than overwhelming peak HP at 6,500 RPM.

This is why you need a COORDINATED package of head porting and cam selection. Not some vague "minimal port work".



A 32 #/HR injector will support about 460 HP at the flywheel. On the other hand, a 36 #/HR injector will support over 500 HP at the flywheel. There is no problem going with a slightly larger injector than you need. It gives you room for future upgrades without buying new injectors. As long as the PCM is programmed with the flow rate and offsets of the specific injectors you use, the fuel injection will operate correctly.



Let's take these together. A 52mm throttle body will support 500 fwHP. The factory LT1 intake will support huge HP. But the intake needs to be ported to support the porting done to the heads. Again, if you have the heads, intake and cam spec'd out by a knowledgeable LT1 head porter, you will get the best results.

Over 500 fwHP a 58mm TB is required. And that means the intake manifold bores have to be opened up to match,

Doesn't affect the engine build.


Injectors were covered above. The stock rails will easily support your HP goals. You will need to upgrade the fuel pump to something like a Walbro 255.



4.10 rear gears would be a significant improvement over the stock 3.42's.


Hopefully you realize you don't need a forged rotating assembly, or even a 383ci build to reach those goals. You can do that on a stock bottom end, with the right heads and cam.


.Eagle claims their kit is good fir 700 HP. With upgrades, even higher. Not sure if I would use that kit at 700 fwHP, but it certainly is not limited to 450 flywheel HP. The stock cast crank, PM rods and hypereutectic pistons can handle your goal.


The Lunati description appears to characterize that as a carb cam.




Confusing - why are you "setting it up for a 200 shot"?

Quote:

I’m told even how stout we are building bottom end it won’t hold boost.

This guy apparently knows nothing about an LT1 block. Throw in a 4-bolt main conversion, and the block can easily support 1,000+ fwHP. Yes, that level take a better crank, rods,, etc. than the Eagle kit. But to say the bottom end will not support boost seems weird.

 

Thank you for the info. I’ve been reading here for a few weeks and your advice is in line with others.
I was told that I needed 4 bolts conversion to run boost by my machinist.
I opted out because I don’t plan on it.

He told me I didn’t have to do the upgraded crank (383) forged assembly etc.

We agreed building the short block to support 600+ would be good if I wanted to change heads later.
I want this to be a one stop shop. I’d consider different rotating assemblies, scat, lunati, etc.
i don’t have interest in dumping 10,000 in this motor.
I agree about the heads and cam. We discussed it but the price just goes up and up.

I’ve spent no money and want to get it all calculated first.
He offered a cheaper rotating asssembly.

It’s still all on the table. Unfortunately I am all over the board but I’ll get to my goals with everyone’s help.

 

Thank you so much friend. I just go off the phone with Lloyd.

 

I just got done having Golen engines build me a 383 with le2 heads, custom cam, and ported intake. I am running 36# injectors and running a 58mm throttle body ( got a really good deal on tpis throttle body I couldn't pass up) 11.5 :1 compression and it made 480 fwhp on the engine dyno. If you want google golen engines adam grossman and you can see the video.

If you want full specs I'll be glad to post them. I wanted to go forced induction but ran out of money to buy a supercharger. So I plan to run this engine for about 3 years and pull it out redo it and put new pistons,cam, and injectors in along with a supercharger.

With the le2 heads, cam, ported intake, injectors, throttle body, torqhead system, golen built and dynoed engine, kooks headers and y pipe I'm in the ball park of about 13k into the engine.

 

I slightly disagree with the statement that mildly ported heads won't support 500hp at the flywheel (raw flow #'s aren't everything). That said, you can't go wrong with a set of LE heads.
Look
180cc head that only flowed 240 cfm (un ported) making 525 hp at 6k and ran low 10s.
11.4:1 CR, 100 octane avgas, and lots of duration on the exhaust lobe to keep making power past peak. Torque monster.
https://www.speed-talk.com/forum/vie...hp?f=1&t=42988

Once you get everything else about the build nailed down, contact Jones cams for a custom grind.

 

Unfortunately, he didn’t say “mildly ported”..... he said “minimal port work on heads mainly the valve job”.

 

you some kind of lawyer?

 

Are you just a wise ***?

He gave his stock aluminum LT1 heads to a “machinist”. The machinist is doing “minimal” porting, which appears to be basically a “valve job”. He is not going to make 450 HP at the flywheel with that approach. But bringing up an example of a significantly different head (CI Vortec Bowtie) has absolutely no relevance to his plan. Best you did was give him false hope that his plan had some sort validity. He needs help, not obfuscation.

You seem very angry and unhappy on this site. Maybe it isn’t the right one for you.

 

The idea was for the OP to read thru that thread (without me writing a book), he might learn something. Also wanted to illustrate that flow numbers aren't the end all beat all. You don't need the 210cc AFRs to make 500 hp.
minimal porting - mild porting - tomato - tomato until someone (OP/machinist) clarifies that
Bowtie vortec is slightly different head IMHO - rather than significantly... after port work on the LT1 head the difference is even less
Never made any claims as to what kind of HP the OP is gonna make.